What is the main ingredient in the Japanese alcoholic drink sake? Rice is the answer.
Sake is brewed primarily from rice, water, yeast, and koji mold. The rice is polished to remove outer layers containing proteins and fats, leaving a starch-rich center that can be converted into fermentable sugars. Koji, usually Aspergillus oryzae grown on steamed rice, supplies enzymes that break the starch down while yeast produces alcohol.
This process makes sake different from beer and wine. Beer generally begins with malted grains whose sugars are already available after mashing, while wine ferments the natural sugars in grapes or other fruit. Sake’s starch conversion and fermentation occur together in the same brewing process, a method known as multiple parallel fermentation.
Sake is often called “rice wine,” but that label is only a rough comparison. It is brewed more like a grain-based beverage than a fruit wine. Common styles include junmai, honjozo, ginjō, and daiginjō, classifications influenced partly by how much the rice has been polished.